Silicone is an organosiloxane polymer with -Si-O-inorganic bond as the skeleton and combined with organic groups (such as alkyl or aryl). Silicone resin has excellent properties such as high temperature resistance, weather aging resistance, water repellency and moisture resistance, high insulation, etc. The development of silicone modified water-based coatings can bring innovative products in a wide range of application fields.

1. Silicone modified water-based alkyd resin. Water-based alkyd resins are cheap and easy to obtain, and have excellent appearance, flexibility and brushability, but poor gloss and color retention and chemical resistance; in addition, the ester bonds of water-based alkyd resins are prone to hydrolysis, resulting in poor water resistance. The grafting of silicone resin or embedding in the main chain can improve the physical and chemical properties of alkyd resin. The early modification is mainly to mix the silicone resin and the alkyd resin that has just been reacted and synthesized in the reaction kettle at high temperature. Simple mixing can also significantly improve the outdoor weather resistance, gloss and color retention of alkyd resin. At present, more modification methods react silicone oligomers with active hydroxyl groups on alkyd resins to prepare silicone-modified alkyd resins, which greatly improves the weather resistance and water resistance of modified alkyd resins. The synthesized water-based alkyd resin is modified by methyltriethoxysilane, and the prepared modified alkyd resin not only maintains the excellent performance of alkyd resin, but also has excellent water resistance, heat resistance and It is safe and non-toxic and meets the needs of environmental protection.

2. Silicone modified water-based polyurethane resin. Although water-based polyurethane coatings have many advantages such as good toughness, wear resistance and strong adhesion, they have disadvantages in water resistance, heat resistance, aging resistance and poor mechanical properties, which limit their application to some extent. The use of silicone resin to modify waterborne polyurethane makes the two complementary advantages, which can meet a wider range of application requirements. The modification method of silicone to polyurethane resin is better by copolymerization modification. 1. Using siloxane (PDMS-G, PDMS-B) to prepare silicone grafted and block-modified waterborne polyurethane (PDMS-G-PUD, PDMS-B-PUD). The study found that the PDMS content or relative molecular weight was positively correlated with the viscosity, particle size and water resistance of the modified water-based polyurethane emulsion; when the relative molecular weight was similar, PDMS-G-PUD had better water resistance and oil resistance than PDMS-B-PUD. Good, with better microphase separation and PDMS surface enrichment, but lower gloss and mechanical properties. 2. Combine the synthesized α, ω-bis(3-methoxy-2-hydroxypropoxypropyl) polydimethylsiloxane and α-N, N-dihydroxyethylaminopropyl-butyl poly Dimethylsiloxane was used as a modifier, and water-based polyurethane dispersions of organosilicon block modification and graft modification were also prepared with PPG, TDI, DMPA, and BDO as raw materials. With the increase of the amount of polysiloxane, the water absorption of the block modified and graft modified waterborne polyurethane films dropped significantly, from 163.9% without modification to 40.2% and 17.3% with 5% modification, the former stretched The performance is reduced, and the latter is the opposite.

3. Silicone modified water-based epoxy resin. Water-based epoxy resin has high film-forming strength, excellent adhesion to many types of substrates, excellent anti-corrosion performance, low price, and high safety; silicone resin grafting can be used to improve its heat resistance, weather resistance, and flexibility Insufficient performance, impact resistance, etc., while endowing epoxy resin with high heat resistance. Based on the synthesis of 9,10-dihydro-9-oxa-10-phosphaphenanthrene-10-oxide (DOPO) modified epoxy resin, phosphorus/ Silicon modified epoxy resin. 4. Silicone modified water-based acrylic resin. Silicone-modified acrylic resins are mainly chemically modified. The hydroxyl-terminated acrylic emulsion or dispersion can be modified by emulsion polymerization or solution polymerization with polyhydroxy silicone oligomers. Studies have shown that the selection and dosage of organosilicon monomers are crucial to the preparation of high-performance modified acrylic resins.

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